Boost Hesitation Hiccup only over 15PSI. Any Ideas?
#18
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maf (sensor) cleaner
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#21
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Just curious here, Joshua and Sid...
Could you explain why a misfire would show up as lean on a WB02?
Thinking logically, if the spark isnt strong enough for whatever reason, you have an incomplete combustion which sends unburnt fuel into the exhaust system. I assume that misfire would cause a rich situation in the exhaust, as i've observed on engines misfiring slightly at idle ( narrow band 02s reading steadily around .6-.8 V )
Thanks
Could you explain why a misfire would show up as lean on a WB02?
Thinking logically, if the spark isnt strong enough for whatever reason, you have an incomplete combustion which sends unburnt fuel into the exhaust system. I assume that misfire would cause a rich situation in the exhaust, as i've observed on engines misfiring slightly at idle ( narrow band 02s reading steadily around .6-.8 V )
Thanks
#22
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The thing to remember is that O2 sensors measure oxygen content in the exhaust, not fuel content...
So incomplete combustion would have an excess of oxygen in the exhaust, because it wasn't used in combustion. The O2 sensor will see this 'extra' oxygen, and therefor display an enlean end condition.
So incomplete combustion would have an excess of oxygen in the exhaust, because it wasn't used in combustion. The O2 sensor will see this 'extra' oxygen, and therefor display an enlean end condition.
#26
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- Coil
- Cap & Rotor
- Leads
- Spark Plugs
Your computer is not part of an ignition system, just controls it..
Any of the 4 will cause a weak spark if not operating properly.
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Why are you running 5's? 7's should be good unless you are running over 18 pounds. What are they gapped at? Sounds like you may need to open the gap a bit if you are having running issues at low load. Also could be dirty or weak injectors, or if you are running super lean.
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Yes, too lean at boost I saw 14:1 at 15psi – but remember that if you have an ignition miss you will see higher O2 content in the exhaust due to unburnt fuel and air. So don’t be misled by the high AFR numbers – it still can be an ignition problem.